<template> 
    <div v-show="list.length">
        <div class="list-control">
            <div class="list-control-filter">
                <span>品牌：</span>
                <span
                    class="list-control-filter-item"
                    :class="{on: item === filterBrand}"
                    v-for="item in brands"
                    @click="handleFilterBrand(item)">{{ item }}</span>
            </div>
            <div class="list-control-filter">
                <span>颜色：</span>
                <span
                    class="list-control-filter-item"
                    :class="{on: item === filterColor}"
                    v-for="item in colors"
                    @click="handleFilterColor(item)">{{ item }}</span>
            </div>
            <div class="list-control-order">
                <span>排序：</span>
                <span
                    class="list-control-order-item"
                    :class="{on: order === ''}"
                    @click="handleOrderDefault">默认</span>
                <span
                    class="list-control-order-item"
                    :class="{on: order === 'sales'}"
                    @click="handleOrderSales">
                    销量
                    <template v-if="order === 'sales'">↓</template>
                </span>
                <span
                    class="list-control-order-item"
                    :class="{on: order.indexOf('cost') > -1}"
                    @click="handleOrderCost">
                    价格
                    <template v-if="order === 'cost-asc'">↑</template>
                    <template v-if="order === 'cost-desc'">↓</template>
                </span>
            </div>
        </div>
          <Product v-for="item in filteredAndOrderedList" :info="item" :key="item.id"></Product>
      <div class="product-not-found" v-show="!filteredAndOrderedList.length">暂无相关商品</div>
    </div>
</template>

<script>
import Product from "./product";
export default {
  components: { Product },
  data() {
    return {
      //排序 sales 销量 cost-desc 价格降序 cost-asc 价格升序
      filterBrand: "",
      filterColor: "",
      order: ""
    };
  },
  computed: {
    brands() {
      return this.$store.getters.brands;
    },
    colors() {
      return this.$store.getters.colors;
    },
    list() {
      //从Vuex中获取数据
      return this.$store.state.productList;
    },
    filteredAndOrderedList() {
      //复制原始数据 Es6语法
      let list = [...this.list];
      //todo 按品牌过滤
      // 按品牌过滤
      if (this.filterBrand !== "") {
        list = list.filter(item => item.brand === this.filterBrand);
      }
      // 按颜色过滤
      if (this.filterColor !== "") {
        list = list.filter(item => item.color === this.filterColor);
      }
      //todo 按颜色过滤
      if (this.order !== "") {
        if (this.order === "sales") {
          list = list.sort((a, b) => b.sales - a.sales);
        } else if (this.order === "cost-desc") {
          list = list.sort((a, b) => b.cost - a.cost);
        } else if (this.order === "cost-asc") {
          list = list.sort((a, b) => a.cost - b.cost);
        }
      }
      return list;
    }
  },
  methods: {
    handleFilterBrand(brand) {
      if (this.filterBrand === brand) {
        this.filterBrand = "";
      } else {
        this.filterBrand = brand;
      }
    },
    handleFilterColor(color) {
      if (this.filterColor === color) {
        this.filterColor = "";
      } else {
        this.filterColor = color;
      }
    },
    handleOrderDefault() {
      this.order = "";
    },
    handleOrderSales() {
      this.order = "sales";
    },
    handleOrderCost() {
      if (this.order === "cost-desc") {
        this.order = "cost-asc";
      } else {
        this.order = "cost-desc";
      }
    }
  },
  //
  mounted() {
    //初始化时，通过Vuex的action请求数据
    this.$store.dispatch("getProductList");
  }
};
</script>

<style scoped>
.list-control {
  background: #fff;
  border-radius: 6px;
  margin: 16px;
  padding: 16px;
  box-shadow: 0 1px 1px rgba(0, 0, 0, 0.2);
}
.list-control-filter {
  margin-bottom: 16px;
}
.list-control-filter-item,
.list-control-order-item {
  cursor: pointer;
  display: inline-block;
  border: 1px solid #e9eaec;
  border-radius: 4px;
  margin-right: 6px;
  padding: 2px 6px;
}
.list-control-filter-item.on,
.list-control-order-item.on {
  background: #f2352e;
  border: 1px solid #f2352e;
  color: #fff;
}
.product-not-found {
  text-align: center;
  padding: 32px;
}
</style>
